Two-dimensional oxide based pressure sensors with high sensitivity

Nanomaterials based pressure sensors have obtained world-wide research interest due to their promising potential applications in health monitoring, artificial intelligence, and electronic skin (e-skin). Despite the recent progress in sensitivity and detection range of the pressure sensors, the relatively high thickness of the active films has obstructed their applications for e-skin and degraded the comfortability as wearable devices. We hereby report for the first time a novel pressure sensor based on two-dimensional metal oxide nanosheets where the gaps between neighboring nanosheets are adjustable. The pressure sensors show a sensitivity of up to 7.2 × 10⁶ kPa^-1, which is the highest value ever reported for a pressure sensor. Additionally, the sensor shows good repeatability and excellent stability. The pressure-sensing ranges can be tuned by adjusting the coverage of the nanosheet film. This work presents an effective strategy to develop ultrathin pressure sensors.